| Virtual compressor outlet temperature sensing for charge air cooler overheating protection -> Monitor Keywords |
|
|
 
Virtual compressor outlet temperature sensing for charge air cooler overheating protectionRelated Patent Categories: Power Plants, Fluid Motor Means Driven By Waste Heat Or By Exhaust Energy From Internal Combustion Engine, With Supercharging Means For Engine, With Means To Change Temperature Of Supercharged FlowVirtual compressor outlet temperature sensing for charge air cooler overheating protection description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20060086089, Virtual compressor outlet temperature sensing for charge air cooler overheating protection. Brief Patent Description - Full Patent Description - Patent Application Claims
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates generally to systems and methods for controlling turbocharger compressor output temperature in a compression-ignition engine and, in particular, to a system and method for determining the temperature of charge air exiting the turbocharger compressor. [0003] 2. Background Art [0004] In a typical compression-ignition engine equipped with an exhaust gas recirculation (EGR) system, a limited amount of exhaust gas is directed into an intake manifold of the engine. This ensures that unused fuel and byproducts are combusted before they are released to the atmosphere, and it also lowers peak combustion temperature to minimize the formation of oxides of nitrogen (NOx). This feature is enhanced by the addition of an EGR cooling system, which reduces the EGR gas temperature before it is introduced into the intake manifold. This increases EGR charge density and reduces overall combustion temperatures and their contribution to the formation of NOx. [0005] In engines so equipped, intake air is commonly compressed and cooled, typically by respectively using a turbocharger compressor and a charge air cooler, to increase power density, that is, the power per swept volume. Added flexibility in the compression of intake air compared with that of a conventional turbocharger compressor is often achieved by using a variable geometry turbocharger (VGT). The flexibility optimizes the turbocharger rotational speed and acceleration, which minimizes turbo lag, the response time required for the turbocharger to begin to affect engine performance following an accelerator actuation. The VGT is typically controlled by an electronic control module (ECM) to supply to the engine amounts of turbo boost that vary depending on various operating conditions. [0006] A concern with compressing intake air is that of overheating the charge air cooler. Accordingly, a dependable and accurate method of determining the output temperature of the compressor is an important factor in preventing such overheating. SUMMARY OF THE INVENTION [0007] The present invention provides a system and method for controlling a compression ignition engine to avoid overheating a charge air cooler. A representative system and method monitor current ambient and engine operating conditions to determine if conditions are favorable for overheating the charge air cooler. If such conditions are detected, the engine is controlled accordingly to avoid overheating. Preferably, the engine is controlled to limit the temperature of the turbocharger compressor output. The present system and method uses a virtual sensor to determine the compressor output temperature, the virtual sensor being defined as a predictive model of an engine used by a microprocessor, in parallel with the real engine, in real time, and using the same real values of sensed ambient and engine operating conditions as does the real engine. [0008] In the present invention, the method for monitoring current ambient conditions includes determining ambient air temperature and ambient pressure. The method for monitoring engine operating conditions includes determining air mass flow rate and turbocharger compressor speed. The method for controlling the engine includes using the monitored ambient and engine condition results to calculate turbocharger compressor output temperature. [0009] A preferred method for calculating turbocharger compressor output temperature (TCO) is to use a virtual TCO sensor based on the following equation, which may be incorporated into an electronic control unit (ECU) . TCO = ATS .times. CF .eta. TT .times. ( P r .gamma. - 1 .gamma. - 1 + .eta. TT ) where: ATS is the temperature of the turbocharger compressor inlet; [0010] .eta..sub.TT is the compressor efficiency; [0011] P.sub.r is the compressor pressure ratio; [0012] .gamma. is the ratio of specific heats; and [0013] CF is the TCO sensor correction factor. [0014] The TCO value is compared with a crucial temperature above which damage to the charge air cooler could occur. If the TCO value is greater than the crucial temperature, the engine is controlled to reduce the turbocharger compressor output temperature to avoid such damage. Preferably, controlling the engine includes at least modifying EGR flow and/or includes at least modifying charge air flow by directing a portion of it to bypass the charge air cooler. BRIEF DESCRIPTION OF THE DRAWINGS [0015] FIG. 1 is a block diagram illustrating a representative system or method for controlling a compression-ignition, internal combustion engine to avoid overheating a charge air cooler according to the present invention; [0016] FIG. 2 is a block diagram illustrating a representative charge air cooler for a compression-ignition engine having a charge air cooler bypass and a turbocharger compressor according to the present invention; and [0017] FIG. 3 is a block diagram illustrating operation of a system or method for controlling a compression-ignition, internal combustion engine to avoid overheating a charge air cooler according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0018] FIG. 1 provides a schematic/block diagram illustrating operation of a system or method for controlling a compression ignition engine to avoid overheating a charge air cooler according to the present invention. The system 10 includes a multicylinder, compression ignition, internal combustion engine, such as a diesel engine 12, which may be installed in a vehicle, generally indicated by reference numeral 14, depending on the particular application. The vehicle 14 includes a tractor, generally indicated by reference numeral 16, and a semitrailer, generally indicated by reference numeral 18. The diesel engine 12 is installed in the tractor 16 and interfaces with various sensors and actuators located on the engine 12, tractor 16, and semitrailer 18 via engine and vehicle wiring harnesses as described in the following in greater detail. In other applications, the engine 12 may be used to operate industrial and construction equipment or in stationary applications for driving generators, compressors, and/or pumps and the like. [0019] An electronic engine control module (ECM) 20 receives signals generated by engine sensors/switches, generally indicated by reference numeral 22, and vehicle sensors, generally indicated by reference numeral 24, and processes the signals to control engine and/or vehicle actuators such as fuel injectors, generally indicated by reference numeral 26. The ECM 20 preferably includes computer-readable storage media, generally indicated by reference numeral 28, for storing data representing instructions executable by a computer 108 to control the engine 12. Computer-readable storage media 28 may also include calibration information in addition to working variables, parameters, and the like. The computer-readable storage media 28 include a random access memory (RAM) 30 in addition to various nonvolatile memory such as read-only memory (ROM) 32, and keep-alive, or nonvolatile, memory (KAM) 34. The computer-readable storage media 28 communicate with a microprocessor 38 and input/output (I/O) circuitry 36 via a standard control/address bus. As will be appreciated by one of ordinary skill in the art, computer-readable storage media 28 may include various types of physical devices for temporary and/or persistent storage of data that include solid state, magnetic, optical, and combination devices. For example, the computer-readable storage media 28 may be implemented using one or more physical devices such as DRAM, PROMS, EPROMS, EEPROMS, flash memory, and the like. Depending on the particular application, computer-readable storage media 28 may also include floppy disks, CD ROM, and the like. [0020] In a typical application, the ECM 20 processes inputs from the engine sensors 22 and the vehicle sensors/switches 24 by executing instructions stored in the computer-readable storage media 28 to generate appropriate output signals for control of the engine 12. The engine sensors 22 include a timing reference sensor (TRS) 40, which provides an indication of crankshaft position and may be used to determine engine speed. An oil pressure sensor (OPS) 42 and an oil temperature sensor (OTS) 44 are used to monitor the pressure and temperature of engine oil respectively. Continue reading about Virtual compressor outlet temperature sensing for charge air cooler overheating protection... Full patent description for Virtual compressor outlet temperature sensing for charge air cooler overheating protection Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Virtual compressor outlet temperature sensing for charge air cooler overheating protection patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Virtual compressor outlet temperature sensing for charge air cooler overheating protection or other areas of interest. ### Previous Patent Application: Communication protocol for a distributed electrohydraulic system having multiple controllers Next Patent Application: Vibration limiter for coaxial shafts and compound turbocharger using same Industry Class: Power plants ### FreshPatents.com Support Thank you for viewing the Virtual compressor outlet temperature sensing for charge air cooler overheating protection patent info. IP-related news and info Results in 0.13123 seconds Other interesting Feshpatents.com categories: Electronics: Semiconductor , Audio , Illumination , Connectors , Crypto , 174 |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
